Returning to the centre of the city, spend an evening on Avenida Corrientes, known as the street that never sleeps, and famous for its many theatres and pizza restaurants.
Pizza in Buenos Aires comes with a lot of cheese, and usually deep pan, but every place offers its own varieties. In most pizzerias, you can eat standing up at the bar, or sitting in the restaurant area. Some of the most popular options are El palacio de la pizza (Av. Corrientes 751), Las Cuartetas (Av. Corrientes 838), La Rey (Av. Corrientes 961), Banchero (Av. Corrientes 1300), Güerrín (Av. Corrientes 1368), Los Inmortales (Av. Corrientes 1369) and El Cuartito (Talcahuano 937).
The big draw on Corrientes is the theatre scene. Most of the city's mainstream theatres are located here and it's advisable to book in advance if you want to catch a show - though there are so many options that you'll usually be able to find tickets for something. Some of the most important theatres are Teatro Metropolitan (Av. Corrientes 1343), Multiteatro (Av. Corrientes 1283), Broadway Theatre (Av. Corrientes 1155), Teatro Apolo (Av Corrientes 1372), Teatro Lola Membrives (Av. Corrientes 1280) and Paseo La Plaza (Av. Corrientes 1660).
A little further afield, you'll find Teatro Cervantes (Av. Córdoba 1155), Teatro Payró (San Martín 766), and Teatro Sarmiento (Av. Sarmiento 2715), and there's a big independent theatre scene in the neighbourhoods of Boedo, Almagro and Villa Crespo - try El Camarín de las Musas (Mario Bravo 960), Espacio Callejón (Humahuaca 3759), Teatro El Perro (Bonpland 800) and Timbre 4 (Av. Boedo 640).